The conclusions by Solomon et al1 about the adverse effects of opioids in elderly patients are based on faulty methodology. They sought to determine adverse effects of opioid prescriptions and “considered subjects as being opioid-exposed from the day after the first dispensing. . . . ”1(p1980) However, if I understand their method correctly, they only tracked outpatient prescriptions. So, if a patient was hospitalized with surgery or an injury, prescribed opioids in the hospital, and continued on opioid therapy on discharge, the day of discharge prescription would be counted as the first opioid exposure in their database and the confounding effect of the prior surgery or injury would be missed.